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1.
2.
Ayon Haro ER, Ukai T, Yokoyama M, Kishimoto T, Yoshinaga Y, Hara Y. Locally administered interferon‐γ accelerates lipopolysaccharide‐induced osteoclastogenesis independent of immunohistological RANKL upregulation. J Periodont Res 2011; 46: 361–373. © 2011 John Wiley & Sons A/S Background and Objective: Interferon‐γ (IFN‐γ) potently inhibits RANKL‐induced osteoclastogenesis in vitro. In contrast, previous studies have shown that an increase in IFN‐γ expression is correlated with an increase in lipopolysaccharide (LPS)‐induced bone loss in vivo. However, it is not clear whether local IFN‐γ accelerates osteoclastogenesis or not in vivo. Therefore, the aim of this study was to clarify the role of local IFN‐γ in LPS‐induced osteoclastogenesis. Material and Methods: We induced bone loss in calvaria by injecting LPS. One group of mice received an IFN‐γ injection together with LPS injection, while another group received IFN‐γ 2 d after LPS injection. Bone resorption was observed histologically. Next, we stimulated murine bone marrow macrophages with macrophage‐colony stimulating factor and RANKL in vitro. We added different doses of IFN‐γ and/or LPS at 0 or 48 h time points. Cells were stained with tartrate‐resistant acid phosphatase at 72 h. Results: Local administration of IFN‐γ together with LPS injection did not affect osteoclast formation. However, IFN‐γ injected after LPS injection accelerated osteoclast formation. Also, we confirmed that IFN‐γ added at 0 h inhibited RANKL‐induced osteoclastogenesis in vitro. However, inhibition by IFN‐γ added at 48 h was reduced compared with that by IFN‐γ added at 0 h. Interestingly, IFN‐γ together with a low concentration of LPS accelerated osteoclast formation when both were added at 48 h compared with no addition of IFN‐γ. Conclusion: The results suggest that local IFN‐γ accelerates osteoclastogenesis in certain conditions of LPS‐induced inflammatory bone loss.  相似文献   
3.
Autologous stem cell transplantation (ASCT) is a treatment option for HIV-positive patients with non-Hodgkin lymphoma (NHL) and multiple myeloma (MM). However, the prognosis after ASCT in HIV-positive Japanese patients remains unclear. The aim of this study was to evaluate the impact of HIV infection on transplant outcomes after ASCT in Japan. Using the national database of the Japan Society for Hematopoietic Cell Transplantation, we retrospectively evaluated patients with NHL (n?=?3862) and MM (n?=?2670) who underwent their first ASCT between 2001 and 2014. The presence of HIV antibody was used to diagnose HIV infection. Fifty-six patients with NHL (1.4%) and 23 with MM (.8%) were positive for HIV antibody. Among patients with NHL overall survival (OS) was lower in HIV-positive patients than in HIV-negative patients (5-year OS: HIV-positive patients, 44% versus HIV-negative patients, 65%; P?<?.001). In a multivariate analysis HIV infection was significantly associated with an increased risk of overall mortality (hazard ratio, 2.30; P?<?.001). The incidence of relapse was higher in HIV-positive patients (P?=?.036), whereas there was a similar incidence of nonrelapse mortality (P?=?.879). OS in patients with MM was similar between those with/without HIV infection (5-year OS: HIV-positive patients, 61% versus HIV-negative patients, 63%; P?=?.988). HIV infection was associated with a higher risk of overall mortality and relapse after ASCT for NHL in a Japanese population.  相似文献   
4.

Background

Adenosine-to-inosine (A-to-I) RNA editing is catalyzed by adenosine deaminases acting on RNA (ADAR) enzymes. Recent evidence suggests that RNA editing of antizyme inhibitor 1 (AZIN1) RNA is emerging as a key epigenetic alteration underlying cancer pathogenesis.

Methods

We evaluated AZIN1 RNA editing levels, and the expression of its regulator, ADAR1, in 280 gastric tissues from 140 patients, using a RNA editing site-specific quantitative polymerase chain reaction assays. We also analyzed the clinical significance of these results as disease biomarkers in gastric cancer (GC) patients.

Results

Both AZIN1 RNA editing levels and ADAR1 expression were significantly elevated in GC tissues compared with matched normal mucosa (P?<?0.0001, 0.0008, respectively); and AZIN1 RNA editing was positively correlated with ADAR1 expression. Elevated expression of ADAR1 significantly correlated with poor overall survival (P?=?0.034), while hyper-edited AZIN1 emerged as an independent prognostic factor for OS and disease-free survival in GC patients [odds ratio (OR):1.98, 95% CI 1.17–3.35, P?=?0.011, OR: 4.55, 95% CI 2.12–9.78, P?=?0.0001, respectively]. Increased AZIN1 RNA editing and ADAR1 over-expression were significantly correlated with key clinicopathological factors, such as advanced T stage, presence of lymph node metastasis, distant metastasis, and higher TNM stages in GC patients. Logistic regression analysis revealed that hyper-editing status of AZIN1 RNA was an independent risk factor for lymph node metastasis in GC patients [hazard ratio (HR):3.03, 95% CI 1.19–7.71, P?=?0.02]. Conclusions: AZIN1 RNA editing levels may be an important prognostic biomarker in GC patients, and may serve as a key clinical decision-making tool for determining preoperative treatment strategies in GC patients.
  相似文献   
5.
Arsenic is the most widespread environmental toxin. Substantial amounts of pentavalent organoarsenicals have been used as herbicides, such as monosodium methylarsonic acid (MSMA), and as growth enhancers for animal husbandry, such as roxarsone (4-hydroxy-3-nitrophenylarsonic acid) [Rox(V)]. These undergo environmental degradation to more toxic inorganic arsenite [As(III)]. We previously demonstrated a two-step pathway of degradation of MSMA to As(III) by microbial communities involving sequential reduction to methylarsonous acid [MAs(III)] by one bacterial species and demethylation from MAs(III) to As(III) by another. In this study, the gene responsible for MAs(III) demethylation was identified from an environmental MAs(III)-demethylating isolate, Bacillus sp. MD1. This gene, termed arsenic inducible gene (arsI), is in an arsenic resistance (ars) operon and encodes a nonheme iron-dependent dioxygenase with C⋅As lyase activity. Heterologous expression of ArsI conferred MAs(III)-demethylating activity and MAs(III) resistance to an arsenic-hypersensitive strain of Escherichia coli, demonstrating that MAs(III) demethylation is a detoxification process. Purified ArsI catalyzes Fe2+-dependent MAs(III) demethylation. In addition, ArsI cleaves the C⋅As bond in trivalent roxarsone and other aromatic arsenicals. ArsI homologs are widely distributed in prokaryotes, and we propose that ArsI-catalyzed organoarsenical degradation has a significant impact on the arsenic biogeocycle. To our knowledge, this is the first report of a molecular mechanism for organoarsenic degradation by a C⋅As lyase.The metalloid arsenic is the most common environmental toxic substance, entering the biosphere primarily from geochemical sources, but also through anthropogenic activities (1). Arsenic is a group 1 human carcinogen that ranks first on the Agency for Toxic Substances and Disease Registry Priority List of Hazardous Substances (www.atsdr.cdc.gov/SPL/index.html). Microbial arsenic transformations create a global arsenic biogeocycle (1). These biotransformations include redox cycles between the relatively innocuous pentavalent arsenate and the considerably more toxic and carcinogenic trivalent arsenite (2, 3). In addition, many microbes, both prokaryotic and eukaryotic, have arsM genes for inorganic arsenite [As(III)] S-adenosylmethionine methyltransferases that methylate inorganic As(III) to mono-, di-, and tri-methylated species (4, 5). The genes encoding arsenic transforming enzymes are widely distributed, and these arsenic biotransformations have been proposed to play significant roles in the arsenic biogeocycle and in remodeling the terrain in volcanic areas such as Yellowstone National Park and regions of the world with high amounts of arsenic in soil and water such as West Bengal and Bangladesh (3, 6).Arsenicals, both inorganic and organic, have been used in agriculture in the United States for more than a century (7). Historically, the use of inorganic arsenical pesticides/herbicides has been largely replaced by methylated arsenicals such as monosodium methylarsonic acid (MSMA), which is still in use as an herbicide for turf maintenance on golf courses, sod farms, and highway rights of way, and for weed control on cotton fields (7). More complex pentavalent aromatic arsenicals such as roxarsone [4-hydroxy-3-nitrophenylarsonic acid, Rox(V)] have been largely used since the middle of the 1940s as antimicrobial growth promoters for poultry and swine to control Coccidioides infections and improve weight gain, feed efficiency, and meat pigmentation (8, 9). These aromatic arsenicals are largely excreted unchanged and introduced into the environment when chicken litter is applied to farmland as fertilizer (8). Pentavalent organoarsenicals are relatively benign and less toxic than inorganic arsenicals; however, aromatic (810) and methyl (11, 12) arsenicals are degraded into more toxic inorganic forms in the environment, which may contaminate the foods and water supplies. Although microbial degradation of environmental organoarsenicals has been documented (8, 9, 11, 13), no molecular details of the reaction have been reported. We recently demonstrated that a microbial community in Florida golf course soil carries out a two-step pathway of MSMA reduction and demethylation (14). Here we report the isolation of an environmental methylarsonous acid [MAs(III)]-demethylating bacterium Bacillus sp. MD1 (for “MAs(III) demethylating”) from Florida golf course soil and the cloning of the gene, termed arsenic inducible gene (arsI), responsible for MAs(III) demethylation. The gene product, ArsI, is nonheme iron-dependent dioxygenase with C⋅As lyase activity. ArsI cleaves the C⋅As bond in a wide range of trivalent organoarsenicals, including the trivalent roxarsone [Rox(III)], into As(III), which strongly suggests that the environmental pentavalent phenylarsenicals such as Rox(V) also undergo a two-step pathway of sequential reduction and ArsI-catalyzed dearylation, in analogy with the demethylation of MSMA by a microbial community. Thus, ArsI-catalyzed C⋅As bond cleavage is a newly identified mechanism for degradation of organoarsenical herbicides and antimicrobial growth promoters.  相似文献   
6.
Journal of Artificial Organs - Online hemodiafiltration (OL-HDF) is a blood purification therapy based on diffusion and ultrafiltration and is classified into two types according to the mode of...  相似文献   
7.
The influence of age on the nocturnal fall in blood pressure (BP) was examined in essential hypertensive patients as well as normal subjects. BP was monitored every 5 min for 24 hr by means of a finger volume oscillometric device. Average daytime BP was similar in the 3 age groups [young: less than 40 (years), n = 49, average daytime systolic BP (ASBP) = 132 +/- 20 mmHg, average daytime diastolic BP (ADBP) = 82 +/- 17 mmHg; adult: 40 less than or equal to less than 60, n = 110, ASBP = 127 +/- 19 mmHg, ADBP = 86 +/- 13 mmHg; old: 60 less than or equal to, n = 33, ASBP = 131 +/- 17 mmHg. ADBP = 83 +/- 11, mean +/- S.D.]. The nocturnal fall in BP was observed in all age groups and its amplitude (delta BP = average daytime BP - average nighttime BP) in the old patients (delta SBP = 13 +/- 11 mmHg, delta DBP = 10 + 8 mmHg) was similar to that in the young patients (delta SBP = 11 +/- 8 mmHg, delta DBP = 10 +/- 8 mmHg). The results suggests that information on the nocturnal behavior of BP is valuable in treating aged essential hypertensives to prevent cerebral and/or myocardial ischemia during sleep.  相似文献   
8.
Three cases from two families with idiopathic hypoparathyroidism and progressive sensorineural deafness are described. Cases 1 and 2 were siblings. Case 3 was one of four siblings from another family. All of them had both idiopathic hypoparathyroidism and progressive sensorineural hearing loss. There was no evidence to suggest involvement of autoimmune mechanism in these cases except for the associated Graves' hyperthyroidism in case 3. Human leukocyte antigen A9 and A11 were positive in both families. The sensorineural hearing loss was progressive even after the treatment for hypoparathyroidism. As the familial idiopathic hypoparathyroidism is a very rare entity, it is unlikely that this disease is associated with familial progressive sensorineural deafness by chance. The combination of these two diseases may compose a new syndrome.  相似文献   
9.
-81 and NE-1 idiotypes (Id) of human nephritogenic anti-DNA antibodies are interspecies Id expressed also in NZB/W F1 mice. We tried to manipulate the synthesis of spontaneously occurring anti-DNA antibody using monoclonal anti-Id antibodies (D1E2 and 1F5) conjugated with a cytotoxic agent, neocarzinostatin (NCS). In vivo administration of anti-Id antibodies conjugated with NCS brought about an improvement in the survival rate of female NZB/W F1 mice. It also caused a retardation of development of lupus nephritis and decreased the numbers of anti-DNA-producing cells. The suppression of anti-DNA antibody synthesis was specific and Id-mediated. The results indicate that the use of a limited number of anti-Id antibodies in combination with a cytotoxic agent may be applicable therapeutically to autoimmune diseases.  相似文献   
10.
To assess the mechanisms how angiotensin II (Ang II) given intracerebroventricularly (i.c.v.) induces natriuresis, the effects of Ang II (10 ng/kg/min, for 30 min) on the renin-angiotensin-aldosterone system, the release of vasopressin (AVP) and atrial natriuretic peptide (ANP) and on cardiovascular and renal functions were investigated in anesthetized dogs. In control dogs, vehicle alone (artificial cerebrospinal fluid) was infused at a rate of 10 microliters/min. Ang II given i.c.v. produced a gradual increase in urine flow, urinary sodium and potassium excretion and osmolar clearance, but had no effect on plasma ANP, aldosterone, arterial blood pressure, and renal blood flow. However, i.c.v. Ang II increased plasma AVP and decreased heart rate, plasma renin activity, inulin clearance and filtration fraction. In the cotrol group, vehicle treatment had no effect on these parameters except for decreases in inulin clearance and filtration fraction. These results suggest that circulating ANP and blood pressure may not play an important role in i.c.v. Ang II-induced natriuresis, but increased AVP release and decreased renal sympathetic nervous activity may contribute to the natriuresis.  相似文献   
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